Unable to set property data in Edge/IE

[hellow554]

SCRIPT5007: Unable to set property 'data' of undefined or null reference in jquery.sse.js (156,32)

MCVE:

var sse = $.SSE("test.php", {
    onMessage: function() {
        sse.stop();
    }
});
sse.start();

Update: I think this is related to the fact, that I do send multiple events per script call, not just one.